JP2012169050A - Lamp for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the illuminance unevenness and color unevenness of a light distribution pattern while securing distance visibility.SOLUTION: This lamp for a vehicle 1 is provided with LEDs 13, 13, and an LD 11, and a phosphor 14 emitting white color light by receiving blue color light emitted from the LEDs 13, 13 and the LD 11. The phosphor 14 has a rear face formed nearly in the same sizes as emission faces of the LEDs 13, 13, is arranged on the emission face so as to cover the entire emission faces of the LEDs 13, 13 with the rear face, and the white color light generated by the blue color light emitted from the LEDs 13, 13 is emitted from the whole surface opposite to the rear face. The LD 11 irradiates blue color light on a laser-irradiated part S emitting white color light to a high-illuminance region Ph in a low-beam area P out of the surface of the phosphor 14.

Description

  The present invention relates to a vehicular lamp.

  In recent years, as a vehicular lamp such as an automobile headlight, an LED (light emitting diode) applied to a light source has begun to be used. Although this type of vehicle lamp is excellent in terms of power consumption and the like, the light distribution pattern (for example, passing) is low because the LED has a lower luminance than other types of light sources such as an HID lamp (high-intensity discharge lamp). In some cases, the illuminance in the vicinity of the cut-off line that illuminates the distant part of the beam) is insufficient and sufficient distant visibility cannot be secured.

  Therefore, for example, in the vehicular lamp described in Patent Document 1, a plurality of LED light sources and phosphors are arranged side by side on a substrate opposed to the rear surface of the projection lens, and light from the LED light sources is mainly distributed as a passing beam. As described above, the area near the cutoff line is illuminated with the light from the phosphor excited by the laser light while illuminating the area other than the vicinity of the cutoff line with the light. According to this vehicular lamp, a light distribution pattern (high distant visibility by satisfying the illuminance in the vicinity of the cut-off line by illuminating the vicinity of the cut-off line by using laser light having a luminance higher than that of the LED light source. (Passing beam) can be formed.

JP 2010-232044

  However, in the vehicular lamp described in Patent Document 1, the LED light source and the phosphor arranged side by side on the substrate form separate areas in the light distribution pattern. Will be reflected on the light distribution pattern. In other words, uneven illumination occurs in the light distribution pattern as a result of the formation of a low illuminance region due to the gap between the vicinity of the cut-off line illuminated by the light from the phosphor and another irradiation region illuminated by the light from the LED light source. End up.

  Moreover, in the vehicle lamp described in Patent Document 1, white light is emitted from the phosphor by mixing blue laser light and yellow light emitted from the phosphor excited by the laser light. When the laser beam is partially irradiated to the phosphor, the laser beam propagates through the phosphor, and the phosphor portion not irradiated with the laser beam is also excited. As a result, white light is properly emitted from the phosphor portion irradiated with the laser light, but yellow light is not sufficiently mixed with the blue laser light from the phosphor portion not irradiated with the laser light. Light will be emitted. Accordingly, the phosphor as a whole emits light having partial color unevenness, and partial color unevenness occurs in the light distribution pattern formed by this light.

  This invention is made | formed in view of the said situation, and makes it a subject to provide the vehicle lamp which can suppress the illumination intensity nonuniformity and color nonuniformity of a light distribution pattern, ensuring distant visibility.

In order to solve the above problems, the invention according to claim 1 is a vehicle lamp,
An LED light source;
A laser light source;
A phosphor that emits visible light in response to excitation light emitted from the LED light source and the laser light source;
With
The phosphor has a back surface formed in substantially the same size as the light emitting surface of the LED light source, and is disposed on the light emitting surface so as to cover the entire light emitting surface of the LED light source with the back surface. Visible light from the excitation light emitted from the light source is emitted from the entire surface opposite to the back surface,
The laser light source irradiates a portion of the surface of the phosphor that emits visible light to a high illuminance region in a light distribution pattern.

The invention according to claim 2 is the vehicle lamp according to claim 1,
Of the phosphor, a portion irradiated with excitation light emitted from the laser light source is thicker than other portions of the phosphor.

The invention according to claim 3 is the vehicle lamp according to claim 1 or 2,
Of the phosphor, the portion irradiated with the excitation light emitted from the laser light source has a higher phosphor concentration than the other portion of the phosphor.

Invention of Claim 4 is a vehicle lamp as described in any one of Claims 1-3,
A reflector that reflects visible light emitted from the phosphor forward;
A projection lens that projects visible light reflected by the reflector to the front of the vehicle;
A shade that blocks a portion of visible light from being reflected by the reflector until entering the projection lens;
It is characterized by providing.

Invention of Claim 5 is a vehicle lamp as described in any one of Claims 1-3,
A light-shielding member is provided in the vicinity of the phosphor so as to cover a part of the surface of the phosphor and shields a part of visible light emitted from the phosphor.

  According to the present invention, the phosphor that receives the excitation light emitted from the LED light source and the laser light source and emits visible light emits visible light from the excitation light emitted from the LED light source on the back side from the surface, Since the laser light source emits excitation light (laser light) to the portion of the phosphor surface that emits visible light to the high-illuminance region in the light distribution pattern, the visible light from the LED light source is emitted from the light distribution pattern. While the main light distribution is, a high illuminance region in the light distribution pattern can be formed by visible light from the phosphor portion that has been brightened by receiving excitation light from the laser light source. Therefore, the required illuminance in the high illuminance region that illuminates the distant area can be satisfied, and sufficient distant visibility can be ensured.

  In addition, the phosphor has a back surface formed in substantially the same size as the light emitting surface of the LED light source, and is disposed on the light emitting surface so as to cover the entire light emitting surface of the LED light source with the back surface of the LED light source. Visible light emitted from the excitation light emitted from the light is emitted from the entire surface opposite to the back surface, so that the excitation light from the LED light source is irradiated over the entire phosphor through the back surface of the phosphor. Accordingly, it is possible to emit visible light that is appropriately mixed color from the entire surface of the phosphor, and to suppress color unevenness of the light distribution pattern.

  In addition, since the phosphor emits visible light from the entire surface, and the laser light source partially irradiates excitation light (laser light) on the surface of the phosphor, the surface of the phosphor forming the light source image of the light distribution pattern is The portion irradiated with the excitation light from the laser light source emits light integrally without having an unnatural low luminance portion while the luminance is increased. Therefore, unlike the conventional case where the LED light source and the phosphor arranged in parallel form separate regions in the light distribution pattern, the formation of a low illuminance region due to the gap between the LED light source and the phosphor is prevented. And uneven illuminance of the light distribution pattern can be suppressed.

It is a front view of the vehicle headlamp in 1st and 3rd embodiment. It is a sectional side view of the vehicle lamp in 1st embodiment. It is a top view of the fluorescent substance in a first embodiment. It is a figure which shows the state by which the blue laser beam was irradiated to the fluorescent substance in 1st embodiment. It is a figure for demonstrating the optical path in the vehicle lamp in 1st embodiment. It is a figure which shows the light distribution pattern formed with the vehicle lamp in 1st embodiment. It is a sectional side view of the vehicle lamp in 2nd embodiment. It is a top view of the fluorescent substance in 2nd embodiment. It is a figure for demonstrating the optical path in the vehicle lamp in 2nd embodiment. It is a sectional side view of the vehicular lamp in a third embodiment. It is a top view of the fluorescent substance in 3rd embodiment. It is a figure for demonstrating the optical path in the vehicle lamp in 3rd embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the following description, unless otherwise specified, the description of “up”, “down”, “front”, “rear”, “left”, and “right” refers to the direction viewed from the vehicle lamp in each embodiment. These are used in correspondence with the descriptions in the drawings.

[1 First embodiment]
FIG. 1 is a front view of a vehicular headlamp 100 including a vehicular lamp 1 according to a first embodiment of the present invention, and FIG. 2 is a side sectional view of the vehicular lamp 1.
As shown in FIG. 1, the vehicle headlamp 100 includes a plurality of vehicle lamps 1,... In a lamp chamber covered front by a translucent cover 101, and the plurality of vehicle lamps 1,. A predetermined light distribution pattern (passing beam) is formed in front of the vehicle by the light emitted from the vehicle.

As shown in FIG. 2, the vehicular lamp 1 is a so-called projector-type lamp, which includes a laser diode (hereinafter referred to as LD) 11, a condenser lens 12, two light emitting diodes (hereinafter referred to as LEDs) 13, 13, a phosphor 14, a reflector 15, a shade 16, and a projection lens 17.
Among these, the LD 11 has an optical axis Ax1 along the front-rear direction, and emits blue laser light as excitation light of the phosphor 14 forward along the optical axis Ax1. The LD 11 has a Gaussian distribution luminance characteristic in which the luminance at the center of the light emitting unit is the highest.

  The condensing lens 12 is disposed in front of the LD 11 and condenses the blue laser light emitted forward from the LD 11 onto the surface (upper surface) of the phosphor 14 disposed further forward. More specifically, the condensing lens 12 condenses the blue laser light from the LD 11 and irradiates the laser irradiation portion S (see FIG. 3) at the substantially central portion of the surface of the phosphor 14. As will be described later, the laser irradiation portion S is a portion that emits white light to the high illuminance region Ph in the light distribution pattern (passing beam P) on the surface of the phosphor 14 (see FIG. 6). .

  Each of the two LEDs 13 and 13 is a 1 mm square LED chip that emits blue light as excitation light of the phosphor 14, and is spaced 0.1 mm in the left-right direction (the direction perpendicular to the paper in FIG. 2). (See FIG. 3). The LEDs 13 and 13 have the upper surface of the metal flat plate 18 so as to be positioned in front of the condensing lens 12 with the light emitting surface of the upper surface tilted backward at an angle of 22.5 degrees with respect to the optical axis Ax1. Is arranged. On the lower surface of the metal flat plate 18, heat radiation fins 181,... For dissipating the heat generated by the LEDs 13, 13 are provided.

3 is a plan view of the phosphor 14, and FIG. 4 is a diagram showing a state in which the phosphor 14 is irradiated with the blue laser light from the LD 11. As shown in FIG.
As shown in these drawings, the phosphor 14 has a surface (upper surface) formed in substantially the same size (front view shape and area) as the entire light emitting surface of the two LEDs 13 and 13 arranged side by side, and It is formed in a flat plate shape having a back surface (lower surface), and is disposed on the light emitting surface of the LEDs 13 and 13 so as to be positioned on the optical axis Ax1. Therefore, the surface of the phosphor 14 is inclined backwards at an angle of 22.5 degrees with respect to the optical axis Ax1 following the light emitting surfaces of the LEDs 13 and 13. More specifically, the phosphor 14 has a front surface and a back surface that are formed in a rectangular shape having four sides obtained by extending the outer sides of the light emitting surfaces of the two LEDs 13 and 13 by 0.05 mm from the ends. , 13 are arranged so as to cover the entire light emitting surface with the back surface. The phosphor 14 is a fluorescent material that emits yellow light when excited by receiving blue light emitted from the LD 11 and the LEDs 13 and 13. When this phosphor 14 receives blue light, white light obtained by mixing blue light and yellow light scattered by the phosphor 14 is emitted radially upward from the surface of the phosphor 14.

  As shown in FIG. 2, the reflector 15 is formed in a curved plate shape that opens downward, and is disposed so as to cover the upper side of the phosphor 14. On the lower surface of the reflector 15, a reflection surface 151 that reflects the white light emitted from the phosphor 14 forward, and a blue laser beam that is regularly reflected by the surface of the phosphor 14 is reflected on the phosphor 14 while being condensed. A condensing reflection surface 152 is formed.

Among these, the reflecting surface 151 is a free-form surface based on a spheroid with the position of the phosphor 14 as the first focal point, and is formed so that the eccentricity gradually increases from the vertical section toward the horizontal section. Has been. The reflecting surface 151 is disposed so as to face the surface (upper surface) of the phosphor 14, and the white light emitted from the phosphor 14 is condensed near the front end of the shade 16 in the vertical section. The light is reflected so as to gradually converge toward the horizontal section.
On the other hand, the condensing / reflecting surface 152 is disposed obliquely above and in front of the phosphor 14 (in the direction of an elevation angle of 45 degrees) and is formed to be continuous with the front end of the reflecting surface 151. The condensing reflection surface 152 is a reflection surface with the position of the phosphor 14 as a focal point. As will be described later, a blue laser that is regularly reflected on the surface of the phosphor 14 without being white light by the phosphor 14. The light is again condensed on the phosphor 14 and irradiated on the laser irradiation portion S on the surface.

  The shade 16 is a light shielding member disposed in front of the phosphor 14. The shade 16 blocks part of white light reflected by the reflecting surface 151 of the reflector 15 to form a cut-off line L of the passing beam P (see FIG. 6). At this time, as will be described later, the shade 16 emits white light so that white light emitted from the laser irradiation portion S of the surface of the phosphor 14 is irradiated to the high illuminance region Ph in the passing beam P. Shield part. Further, the upper surface of the shade 16 is formed at a height substantially coinciding with the optical axis Ax1 and is subjected to aluminum vapor deposition, and the white light reflected by the reflecting surface 151 and incident on the upper surface is projected to the front projection lens. Reflect toward 17.

  The projection lens 17 is an aspheric plano-convex lens having an optical axis Ax2 that coincides with the optical axis Ax1 of the LD 11, and is disposed in front of the reflector 15 and the shade 16. The projection lens 17 has an object-side focal point located in the vicinity of the front end of the shade 16, and reversely projects the white light reflected by the reflecting surface 151 of the reflector 15 and incident on the projection lens 17 to the front of the vehicle.

Next, the operation of the vehicular lamp 1 when forming a light distribution pattern (passing beam) will be described.
FIGS. 5A and 5B are diagrams for explaining an optical path in the vehicular lamp 1. FIG. 6 shows a light distribution pattern formed on a virtual screen in front of the vehicle by the vehicular lamp 1. FIG. It is a figure which shows a passing beam.

  As shown in FIG. 5A, when the LD 11 and the LEDs 13 and 13 are in a light emitting state, the blue laser light emitted from the LD 11 is condensed by the condenser lens 12 and the laser irradiated portion on the surface of the phosphor 14 The blue light emitted from the light emitting surfaces of the LEDs 13 and 13 is incident on the back surface of the phosphor 14 while being irradiated from the rear.

  Among these lights, the blue light from the LEDs 13 and 13 is converted into white light in the process of passing through the phosphor 14 and emitted upward from the surface of the phosphor 14. Here, the front surface and the back surface of the phosphor 14 are formed to have substantially the same size as the entire light emitting surface of the LEDs 13 and 13, and the phosphor 14 emits light so that the entire light emitting surface of the LEDs 13 and 13 is covered with the back surface. Since it is arrange | positioned on the surface, the blue light from LED13,13 is irradiated over the said fluorescent substance 14 whole through the back surface of the fluorescent substance 14. FIG. Therefore, the white light by the blue light from the LEDs 13 and 13 is emitted from the entire surface of the phosphor 14.

  On the other hand, most of the blue laser light from the LD 11 is converted into white light by the phosphor 14 and emitted upward from the laser irradiation portion S on the surface, but a part of the blue laser light is not white and the surface of the phosphor 14 is inclined. So that it is specularly reflected obliquely upward and forward. Part of the blue laser light specularly reflected on the surface of the phosphor 14 is condensed again on the phosphor 14 by the condensing reflection surface 152 of the reflector 15, and is irradiated on the laser irradiation portion S on the surface to be white light. The At this time, the laser irradiation portion S emits white light by blue laser light having a luminance higher than that of the blue light from the LED 13 and also emits white light by blue light from the LED 13. It emits light with a higher brightness than the part. In addition, as described above, white light is emitted from the entire surface of the phosphor 14, and only the laser irradiation portion S of the surface is irradiated with blue laser light. Therefore, the surface of the phosphor 14 is irradiated with laser light. While the brightness of the portion S is increased, the light is integrally emitted without having an unnatural low brightness portion.

  As shown in FIG. 5B, the white light emitted upward from the phosphor 14 is reflected forward by the reflecting surface 151 of the reflector 15 and irradiated from the projection lens 17 forward of the vehicle. At this time, a part of the white light incident on the lower part of the projection lens 17 is shielded by the shade 16, so that the passing beam P in which the irradiation light above the cutoff line L is blocked as shown in FIG. It is formed. Further, at this time, white light from the laser irradiation portion S that has been brightened with blue laser light is irradiated in the vicinity of the cut-off line L in the passing beam P, and a high illuminance region Ph is formed in the vicinity of the cut-off line L. .

  As described above, according to the vehicular lamp 1, the white light generated by the blue light from the LEDs 13, 13 is used as the main light distribution of the passing beam P, and the laser irradiation is enhanced by receiving the blue laser light from the LD 11. A high illuminance region Ph in the passing beam P can be formed by the white light from the portion S. Therefore, it is possible to satisfy the required illuminance of the high illuminance region Ph that illuminates a distant place, and to ensure sufficient distant visibility.

  Further, since the blue light from the LEDs 13 and 13 is irradiated over the entire phosphor 14 through the back surface of the phosphor 14, the appropriately mixed white light can be emitted from the entire surface of the phosphor 14, Color unevenness of the passing beam P can be suppressed.

  Further, the surface of the phosphor 14 that forms the light source image of the passing beam P emits light integrally without having an unnatural low luminance portion while the laser irradiation portion S has a high luminance. Therefore, unlike the conventional case where the LED light source and the phosphor arranged in parallel form separate regions in the light distribution pattern, the formation of a low illuminance region due to the gap between the LED light source and the phosphor is prevented. And unevenness in illumination of the passing beam P can be suppressed.

[2 Second Embodiment]
Next, a second embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected to the component similar to said 1st embodiment, and the description is abbreviate | omitted.

FIG. 7 is a side sectional view of the vehicular lamp 2 according to the second embodiment of the present invention.
As shown in this figure, the vehicular lamp 2 is a so-called parabolic lamp, and includes two LEDs 23 and 23 in addition to the LD 11 and the condenser lens 12 configured in the same manner as in the first embodiment. A phosphor 24 and a reflector 25 are provided.

  Among these, the two LEDs 23 and 23 are arranged side by side in the left-right direction (the direction perpendicular to the paper surface in FIG. 7), and the light emitting surface on the upper surface forms an angle of 27.5 degrees with respect to the optical axis Ax1. And tilted backwards. The configuration of the LEDs 23 and 23 other than this point is the same as the configuration of the LEDs 13 and 13 in the first embodiment.

FIG. 8 is a plan view of the phosphor 24.
As shown in this figure, the phosphor 24 is configured in substantially the same manner as the phosphor 14 in the first embodiment. However, the phosphor 24 is disposed so that blue laser light is irradiated to the laser irradiation portion S closer to the lower side of the surface. Further, the lower end of the surface of the phosphor 24 from the laser irradiation portion S is covered with a light shielding mask 241.

As shown in FIG. 7, the reflector 25 is formed in a curved plate shape that opens downward, and is disposed so as to cover the upper side of the phosphor 24. On the lower surface of the reflector 25, a reflection surface 251 that reflects the white light emitted from the phosphor 24 forward, and a blue laser beam that is regularly reflected on the surface of the phosphor 24 is reflected on the phosphor 24 while being condensed. A condensing reflection surface 252 is formed.
Among these, the reflecting surface 251 is a free-form surface based on a rotating paraboloid focusing on the position of the phosphor 24, and is disposed so as to face the surface (upper surface) of the phosphor 24.
On the other hand, the condensing / reflecting surface 252 is disposed obliquely in front of the phosphor 24 (in the direction of an elevation angle of 55 degrees) and is formed to be continuous with the front end of the reflecting surface 251. The condensing / reflecting surface 252 is a reflecting surface with the position of the phosphor 24 as a focal point.

Next, the operation of the vehicular lamp 2 when forming a light distribution pattern (passing beam) will be described.
FIGS. 9A and 9B are diagrams for explaining an optical path in the vehicular lamp 2.

  As shown in FIG. 9A, when the LD 11 and the LEDs 23 and 23 are in a light emitting state, the blue laser light emitted from the LD 11 is condensed by the condenser lens 12 and the laser irradiated portion on the surface of the phosphor 24 The blue light emitted from the light emitting surfaces of the LEDs 23 and 23 is incident on the back surface of the phosphor 24 while irradiating S from behind.

  Among these lights, the blue light from the LEDs 23 and 23 is converted into white light in the process of passing through the phosphor 24 and is emitted upward from the surface of the phosphor 24. At this time, similarly to the phosphor 14 in the first embodiment, the phosphor 24 is irradiated with the blue light from the LEDs 23 and 23 over the entire phosphor 24, and thus the blue color from the LEDs 23 and 23 is emitted. White light is emitted from the entire surface.

  On the other hand, most of the blue laser light from the LD 11 is converted into white light by the phosphor 24 and emitted upward from the laser irradiation portion S on the surface, but a part of the blue laser light is not white and the inclined surface of the phosphor 24 is inclined. So that it is specularly reflected obliquely upward and forward. A part of the blue laser light specularly reflected on the surface of the phosphor 24 is condensed again on the phosphor 24 by the condensing reflection surface 152 of the reflector 15 and irradiated to the laser irradiation portion S on the surface to be white light. The At this time, the laser irradiated portion S emits light with higher luminance than the other portions on the surface of the phosphor 24, similarly to the laser irradiated portion S in the first embodiment. The surface of the phosphor 24 emits light integrally without having an unnatural low-luminance part, like the surface of the phosphor 14 in the first embodiment.

  As shown in FIG. 9B, the white light emitted upward from the phosphor 24 is reflected forward by the reflecting surface 251 of the reflector 25 and is irradiated forward of the vehicle. At this time, a part of the white light emitted from the surface of the phosphor 24 is shielded by the light shielding mask 241, so that the irradiation beam above the cutoff line L is blocked as shown in FIG. P is formed. Further, at this time, white light from the laser irradiation portion S that has been brightened with blue laser light is irradiated in the vicinity of the cut-off line L in the passing beam P, and a high illuminance region Ph is formed in the vicinity of the cut-off line L. .

  Also with the above vehicle lamp 2, the same effect as the vehicle lamp 1 in the first embodiment can be obtained.

[3 Third Embodiment]
Subsequently, a third embodiment of the present invention will be described.

FIG. 10 is a side sectional view of the vehicular lamp 3 according to the third embodiment of the present invention.
As shown in this figure, the vehicular lamp 3 is a so-called direct projection type lamp, and includes an LD 31, a condenser lens 32, two LEDs 33 and 33, a phosphor 34, and a projection lens 37. ing.
Among these, the LD 31 has an optical axis Ax1 that is directed obliquely upward to the rear, and emits blue laser light as excitation light of the phosphor 34 obliquely upward and rearward along the optical axis Ax1. The LD 11 has a Gaussian distribution luminance characteristic in which the luminance at the center of the light emitting unit is the highest.

  The condensing lens 32 is disposed on the optical axis Ax1 obliquely above the LD 31, and the blue laser light emitted from the LD 31 obliquely upward to the rear is further applied to the surface (front surface) of the phosphor 34 disposed obliquely above the rear. Collect light. More specifically, the condensing lens 32 condenses the blue laser light from the LD 31 and irradiates the laser irradiation portion S (see FIG. 11) closer to the lower side of the surface of the phosphor 34.

  Each of the two LEDs 33 and 33 is a 1 mm square LED chip that emits blue light as the excitation light of the phosphor 34, and is spaced 0.1 mm in the left-right direction (the direction perpendicular to the paper in FIG. 10). (See FIG. 11). The LEDs 33 and 33 are supported on the metal flat plate 38 on the rear surface so that the light emitting surface is directed forward and located on the optical axis Ax1 obliquely above and behind the condenser lens 32. The metal flat plate 38 is erected so as to be orthogonal to the front-rear direction, supports the LEDs 33, 33 on the front surface, and has heat radiation fins 381,.

FIG. 11 is a plan view of the phosphor 34.
As shown in this figure, the phosphor 34 is a phosphor material similar to the phosphor 14 in the first embodiment, and is disposed on the light emitting surface of the LEDs 33 and 33 so as to be positioned on the optical axis Ax1. Yes. The phosphor 34 is configured in the same manner as the phosphor 14 in the first embodiment with respect to the arrangement and shape of the LEDs 33 and 33, and covers the entire light emitting surface of the LEDs 33 and 33 with the back surface (rear surface). And the surface is directed forward. Further, the lower end of the surface of the phosphor 34 from the laser irradiation portion S is covered with a light shielding member 341 disposed in the vicinity of the phosphor 34. The light shielding member 341 is formed in an L shape in a side view, and a base end portion is fixed to the metal flat plate 38.

  As shown in FIG. 10, the projection lens 37 is an aspherical plano-convex lens having an optical axis Ax2 along the front-rear direction, and is disposed in front of the phosphor 34 so that the phosphor 34 is located on the optical axis Ax2. Has been. The projection lens 37 has an object-side focal point located in the vicinity of the phosphor 34, and reversely projects white light emitted from the surface of the phosphor 34 to the front of the vehicle.

Next, the operation of the vehicular lamp 3 when forming a light distribution pattern (passing beam) will be described.
FIGS. 12A and 12B are diagrams for explaining an optical path in the vehicular lamp 3.

  As shown in FIG. 12A, when the LD 31 and the LEDs 33 and 33 are in a light emitting state, the blue laser light emitted from the LD 31 is condensed by the condenser lens 32 and the laser irradiated portion on the surface of the phosphor 34 Blue light emitted from the light emitting surfaces of the LEDs 33 and 33 is incident on the back surface of the phosphor 34 while being irradiated with S.

  Among these lights, the blue light from the LEDs 33 and 33 is converted into white light in the process of passing through the phosphor 34 and is emitted forward from the surface of the phosphor 34. At this time, the phosphor 34 is irradiated with the blue light from the LEDs 33 and 33 over the entire phosphor 34 as in the phosphor 14 in the first embodiment. White light is emitted from the entire surface.

  On the other hand, the blue laser light from the LD 31 is converted into white light by the phosphor 34 and emitted forward from the laser irradiation portion S on the surface. At this time, the laser irradiated portion S emits light with higher brightness than the other portions of the surface of the phosphor 34, similarly to the laser irradiated portion S in the first embodiment. Further, the surface of the phosphor 34 emits light integrally without having an unnatural low luminance portion, like the surface of the phosphor 14 in the first embodiment.

  The white light emitted forward from the phosphor 34 is irradiated forward of the vehicle through the projection lens 37 as shown in FIG. At this time, a part of white light emitted from the surface of the phosphor 34 is shielded by the light shielding member 341, so that a passing beam in which the irradiation light above the cutoff line L is shielded as shown in FIG. P is formed. Further, at this time, white light from the laser irradiation portion S that has been brightened with blue laser light is irradiated in the vicinity of the cut-off line L in the passing beam P, and a high illuminance region Ph is formed in the vicinity of the cut-off line L. .

  Also with the above vehicle lamp 3, the same effect as the vehicle lamp 1 in the first embodiment can be obtained.

  It should be noted that the present invention should not be construed as being limited to the first to third embodiments described above, and of course can be modified or improved as appropriate.

  For example, in the first to third embodiments, the vehicular lamps 1 to 3 all form the passing beam P. However, the present invention can also be applied to a vehicular lamp that forms a traveling beam. is there.

  Further, the LDs 11 and 31 emit blue light, and the phosphors 14 to 34 emit yellow light by the blue light. However, the present invention is not limited to this, and other configurations (excitation light and fluorescence) can be obtained. Combination with the body). Furthermore, the light emitted from the phosphors 14 to 34 is not limited to white light, and may be visible light of other colors.

  In addition, the phosphors 14 to 34 are formed in a flat plate shape, but depending on the intensity distribution of the blue light to be emitted, white light with uneven color may be emitted. It is preferable to have a thickness distribution. In this case, the phosphors 14 to 34 are formed so that the thickness from the back surface to the front surface becomes thicker as the blue light intensity irradiated to the phosphors 14 to 34 is higher. Therefore, it is preferable that the thickness of the phosphors 14 to 34 in the laser irradiation portion S is thicker than the thickness of the phosphors 14 to 34 in the other surface portions. Moreover, since LD11,31 has the luminance characteristic of Gaussian distribution, the thickness of the fluorescent substance 14-34 in the laser irradiation part S irradiated with the blue laser beam from LD11,31 is from a peripheral part. It is preferable that the thickness increases toward the center.

  In addition, the phosphors 14 to 34 have a phosphor concentration (the concentration of phosphor particles in the binder) according to the intensity distribution of the emitted blue light in order to suppress the color unevenness of the white light as described above. It is preferable to have. In this case, the phosphors 14 to 34 are formed so that the phosphor concentration is higher in the portion where the intensity of the emitted blue light is higher. Therefore, in the phosphors 14 to 34, it is preferable that the portions irradiated with the blue light from the LDs 11 and 31 have a higher phosphor concentration than the other portions of the phosphors 14 to 34.

In addition, the phosphors 14 to 34 are formed so that the surface thereof is substantially the same size as the entire light emitting surface of the LEDs 13 to 33 (the shape of the front view and its area). It is not limited to this as long as it is formed so as to emit light from the entire surface.
For example, fluorescent substance 14-34 is good also as a shape where the surface is larger than the whole light emission surface of LED13-33, and the back surface and the surface are connected via the taper-shaped surrounding surface. Even in such a shape of the phosphors 14 to 34, the blue light emitted radially from the light emitting surfaces of the LEDs 13 to 33 can be suitably received, and the white light by the blue light can be emitted from the entire surface. . In this case, the entire light emitting surface including the side surfaces of the LEDs 13 to 33 may be covered with the back surfaces of the phosphors 14 to 34 (the entire end surface on the back surface side). If it does in this way, the blue light radiate | emitted from the side surface of LED13-33 will also be taken in in fluorescent substance 14-34, and will be internally reflected toward the surface by a taper-shaped peripheral surface, and the periphery of the surface as white light The light can be emitted from the part.

  In addition, although two LEDs 13 to 33 are arranged side by side, three or more LEDs may be arranged side by side or of course only one. When three or more LEDs 13 to 33 are arranged side by side, the phosphors 14 to 34 are arranged so as to cover the entire light emitting surface of all the LEDs 13 to 33 arranged side by side.

1,2,3 Vehicle lamp 11, 31 LD (Laser light source)
Ax1 Optical axes 12, 32 Condensing lenses 13, 23, 33 LED (LED light source)
14, 24, 34 Fluorescent substance S Laser irradiation part 15, 25 Reflector 151, 251 Reflecting surface 152, 252 Condensing reflecting surface 16 Shade 17, 37 Projection lens Ax2 Optical axis 241 Shading mask (shading member)
341 Light blocking member P Passing beam (light distribution pattern)
L Cut-off line Ph High illumination area

Claims (5)

An LED light source;
A laser light source;
A phosphor that emits visible light in response to excitation light emitted from the LED light source and the laser light source;
With
The phosphor has a back surface formed in substantially the same size as the light emitting surface of the LED light source, and is disposed on the light emitting surface so as to cover the entire light emitting surface of the LED light source with the back surface. Visible light from the excitation light emitted from the light source is emitted from the entire surface opposite to the back surface,
The said laser light source irradiates excitation light to the part which radiate | emits visible light to the high illumination intensity area | region in the light distribution pattern among the surfaces of the said fluorescent substance, The vehicle lamp characterized by the above-mentioned.   2. The vehicular lamp according to claim 1, wherein a portion of the phosphor that is irradiated with excitation light emitted from the laser light source is thicker than other portions of the phosphor.   3. The vehicle according to claim 1, wherein a portion of the phosphor that is irradiated with excitation light emitted from the laser light source has a phosphor concentration higher than other portions of the phosphor. Lamps. A reflector that reflects visible light emitted from the phosphor forward;
A projection lens that projects visible light reflected by the reflector to the front of the vehicle;
A shade that blocks a portion of visible light from being reflected by the reflector until entering the projection lens;
The vehicular lamp according to any one of claims 1 to 3, wherein the vehicular lamp is provided.   The light-shielding member which is arrange | positioned in the vicinity of the said fluorescent substance so that a part of surface of the said fluorescent substance may be covered, and shields a part of visible light radiate | emitted from the said fluorescent substance is provided. 4. The vehicular lamp according to any one of 3.

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